Pedrero-Méndez Alberto, Cesarini Marco, Mendoza-Salido David, Petrucci Arianna, Sarrocco Sabrina, Monte Enrique, Hermosa Rosa
Institute for Agribiotechnology Research (CIALE), Department of Microbiology and Genetics, University of Salamanca, C/ Duero 12, Campus Villamayor-Parque Científico, Villamayor, Salamanca 37185, Spain.
Department of Agriculture, Food and Environment, University of Pisa, Via del Borghetto 80, Pisa 56124, Italy.
Microbiol Res. 2025 Jul;296:128153. doi: 10.1016/j.micres.2025.128153. Epub 2025 Mar 27.
Fusarium head blight (FHB), caused by Fusarium graminearum (Fg), is a major disease of wheat not only due to crop yield losses but also because of food safety concerns, since Fg produces toxic trichotecenes, such as deoxynivalenol (DON). Different Trichoderma strains have shown biocontrol efficacy against various Fusarium spp. in a wide variety of pathosystems. In this work, the efficacy of T. asperellum T25, T. harzianum T136 and T. simmonsii T137, was assessed against Fg ITEM 124 in in vitro tests, which included dual cultures, as well as cellulose and cellophane membrane assays. The three Trichoderma strains inhibited Fg growth to varying degrees. However, only T25 and T136 demonstrated control of FHB in wheat when applied to spikes. By quantitative real-time PCR (qPCR) we analysed the expression of eight plant defence-related marker genes in wheat spikes inoculated with Trichoderma, or not, and subsequently infected with Fg. Only wheat spikes pre-treated with T25 or T136 look to activate the salicylic acid-dependent defence, in response to pathogen infection. Expression of tri genes, involved in DON biosynthesis, was analysed by qPCR in dual-culture Trichoderma-Fg confrontations in two different media, and in the plant spikes. Confrontation results indicated that tri gene expression depends on the Trichoderma strain and the culture medium, but the three Trichoderma strains reduced the expression of tri5 in the plant. Results show that T. asperellum T25 reduced FHB disease index by more than 60 %, and was the most effective biocontrol agent, employing direct mechanisms to limit Fg growth and indirect mechanisms by priming local plant defences.
由禾谷镰刀菌（Fg）引起的小麦赤霉病（FHB）是小麦的一种主要病害，不仅会导致作物减产，还因食品安全问题备受关注，因为Fg会产生脱氧雪腐镰刀菌烯醇（DON）等有毒单端孢霉烯族毒素。不同木霉菌株已在多种病害系统中显示出对各种镰刀菌的生物防治效果。在本研究中，通过体外试验评估了棘孢木霉T25、哈茨木霉T136和西姆斯木霉T137对Fg ITEM 124的防治效果，试验包括对峙培养以及纤维素和玻璃纸膜试验。这三种木霉菌株均不同程度地抑制了Fg的生长。然而，只有T25和T136在应用于麦穗时表现出对小麦赤霉病的防治效果。通过定量实时PCR（qPCR），我们分析了接种或未接种木霉菌、随后感染Fg的小麦麦穗中八个植物防御相关标记基因的表达。只有预先用T25或T136处理的小麦麦穗在病原体感染时似乎激活了水杨酸依赖性防御。通过qPCR分析了在两种不同培养基以及植物麦穗中的木霉-Fg对峙培养中参与DON生物合成的tri基因的表达。对峙培养结果表明，tri基因的表达取决于木霉菌株和培养基，但这三种木霉菌株均降低了植物中tri5的表达。结果表明，棘孢木霉T25使小麦赤霉病病情指数降低了60%以上，是最有效的生物防治剂，它通过直接机制限制Fg生长，并通过激发局部植物防御的间接机制发挥作用。
